Electric interlocking machine



p 27, 1932- v N. L. DONOVAN ET AL 1,830,034

ELECTRIC INTERLOCKING MACHINE Filed March 26, 1925 2 Sheets-Sheet 1 W, Y7 v I l2, amen 60m Sept. 27, 1932. N. L. DONOVAN ET AL 1,880,034

ELECTRIC INTERLOCKING MACHINE Filed March 26,1925 2 Sheets-Sheet 2 W @MMPatented Sept. 27, 1932 .Eifi PAN? NORMAN L. DONOVAN AND CLARENCE E.LAKE, OF JERSEY CITY, NEW JERSEY, AS- SIGNORS TO THE UNION SWITCH &SIGNAL COMIPANY, F SWISSVALE, PENNSYL- VANIA, A CORPORATION OFPENNSYLVANIA ELECTRIC INTERLOCKING MACHINE Application filed March 26,1925. Serial No. 18,478.

Our invention relates to electric interlocking machines, and isparticularly adapted for, though not limited to, the control of railwaytrack switches and signals in a railway switching or interlockinglayout.

One feature of our invention is the proviour invention.

Referring to the drawings, the reference character 24 designates anauxiliary railway track connected with a main railway track by switch25. The sections, insulated from adjoining portions of these tracks,shown in Fig. 1 of the drawings, are provided with a track circuit,which is supplied with current by a battery 124 connected across therails adjacent one end of the main track section, and which includes atrack relay connected across thc rails adjacent the other end of thesame section. Track relay 20 controls two contacts 51 and 108,respectively, both of which are closed when track relay 20 is energizedand both of which are opened when track relay 20 becomes deenergized.

A signal, designated by the reference character 29, governs traflicmovements to the right over the section of main track while switch is inthe normal position shown in Fig. l A second signal, designated by thereference character 30, governs trafiic movements to the left along themain track when switch-25 is in the normal position, or governs trafficmovements onto auxiliary track 24 when switch 25 is in the reverseposition. As here shown each of these signals is of the semaphore type.

Switch 25 is moved between its normal and reverse positions byamechanism 44 which is operated by a pneumatically operated piston andcylinder device 26. The operation of device 26 is controlled by a slidevalve mechanism 28 of a type well known in the art and which iscontrolled by normal and reverse control magnets 80 and 81,respectively, and by a lock magnet 7 8. These three magnets arecontrolled by a manually movable switch control lever 2.

Signals 29 and 30 are controlled by a manually movable signal lever 4which is interlocked electrically, but not mechanically, with switchlever 2. These levers may be arranged together in a suitable locationsuch, for example, as an interlocking tower.

A switch indication device, designated by the reference character 67,comprises a pneu matically operated piston mechanism 7 5, and a rotoroperated by mechanism 7 5 and carrying contact bars 85 and 86. Pistonmechanism is controlled by normal and reverse control magnets and 81 sothat when magnet 80 or magnet 81 becomes energized for causing anoperation of switch 25 to its. normal or its reverse position,respectively, piston mechanism 75 immediately moves contact bars 85 and86 to corresponding positions. As shown in the drawings,

magnet 80 is energized and magnet 81 is deenergized. Under theseconditions, bars 85 are held in a position in which they connectconductors 87 and 88 with conductors 95. When magnet 80 becomesdeenergized and magnet 81 becomes energized, bars 85 become disconnectedfrom wires 87 and 88, and

bars 86 then'connect conductors 87 and 88 with contact springs 97 of asecond switch indication device which is designated by the referencecharacter 27. v

' The second switch indication device 27 is operated by switch mechanism44. Device 27 comprises contact springs 96 and 97, and a rotor carryingcircuit closing contact bars 89 and 91 and circuit shunting bars and 92.

Switch indication device 27 is so connected with switch operatingmechanism 44 as to be operated only when mechanism 44 is just completinga movement of switch 25 to its normal or its reverse position. Withswitch 25 in the normal position, as shown in Fig. 1", switch mechanism44 has caused circuit clos ing bars 91 to be moved away from contactsprings 97, has caused circuit shunting bar 92 to be connected acrosssprings 97, has caused circuit shunting bar 90 to be disco-nnected fromcontact springs 96', and has caused circuit closing bars 89 to connectcontact springs 96 with wires 93 and 94. hen mechanism 44 is completinga movement of switch 25 to the reverse position,.indication device 27becomes operated to remove circuit closing bars 89 from contact springs96,to connect shunting bar 90' across springs 96, to remove shunting bar92 from springs 97, and to causecircuit closing bars 91 toconnectcontact springs 97 with wires 93 and 94. A polarized switch indicationrelay is designated by the term polarized relay. This relay has acontrol Winding 21, and operates a neutral contact 22 and two polarcontacts 23 and 98. Energization of this relay in normal or reversedirection by a source of current, not shown in the drawings but whichhas a positive terminal 13+ and a negative terminal-B, is controlledjointly by switch indication devices 27 and 67. The polarized relaybecomes energized in one direction or. the other only when the positionsof the contact bars of device 27 correspond with the positions of thecontact bars of device 67. At other times, for example when switch 25 isbeing moved from one of its extreme positions to the other, terminals Band B- are disconnected from the polarized relay, and shunting bar 90 orshunting bar 92 is connected across the winding 21 of this relay throughbars 85 or 86, respectively, of device 67 I The normal position ofsignal control lever 4 is as shown in solid lines in the drawings. Lever4, when moved to the position shown a in dash lines to the right of itsnormal position, controls movement of the arm of signal 29 to theproceed position. Lever 4, when moved to the position shown in dashlines to the left of the normal position, similarly controls movement ofthe arm of'signal 30 tothe proceed position.

The normal position of switch'control lever 2 is shown in solid lines inFig. 1. With lever 2 in this position, switch 25 remains in the normalposition shown in Fig. 1 Lever 2, when moved to its reverse position,indicated by dash lines to the right of its normal position, controlsmovement of switch 25 to its reverse position.

Lever 4 is rigidly connected wit-l1 a shaft 3, and lever 2 is rigidlyconnected with a shaft 1. Shafts 1 and 3 could, for correspondingmovements, if desired, instead of being directly connected to the leversas indicated, be connected with levers 2 and 4 through bevelled gears inorder to be arranged other-V Wise than in the horizontal position.Rigidly carried on each of the shafts 1 and 3, is a roller 5 whichcarries a pluralit'y of contact bands for controlling a plurality ofelectric circuits. Contacts 42 and 78, thus operated by roller 5 oflever 2, complete corresponding circuits when lever 2 is in the normalposition shown in the drawings; and contacts 83 and 100, also operatedby roller 5 of lever 2, complete corresponding circuits when lever 2 ismoved to its reverse position. Contacts 34, 106,54 and 64, operated byroller 5 of lever 4, complete corresponding circuits when lever 4 is inits normal position as shown in the drawings; contacts 65, 128 and 118,operated by roller 5 of lever 4, complete corresponding circuits whenlever 4 is moved to its reverse position to the left; and contacts 55,121 and 116, operated by roller 5 of lever 4, complete their circuitswhen lever 4 is moved to its reverse position to the right.

The handle of each of the levers 2 and 4 is provided with means formanually closing auxiliary contacts of the type known in the art aslatch contacts. These contacts are operable by a towerman withoutmovement of the lever 2 or 4 with which they are associated. Contacts ofthis type associated with lever 2 are designated by the referencecharacters 16 and 17. A contact of this type associated with lever 4 isdesignated by the reference character 15.

Each of the levers 2 and 4 is provided with two electric locks which aresimilar to the indication locks well known in the art but which are hereshown controlled by novel and improved means. The locks for lever 2 aredesignated prin1ary lock and secondary lock. Each of these lockscomprises a segment 6 and an electromagnet 12. Each of the segments 6 isrigidly connected with, and operated by, shaft 1 oflever 2. Each of themagnets 12, upon becoming energized, moves a dog 10 out of engagementwith a projection 8 of its segment 6. When the magnets 12 aredeenergized as here shown, dogs 10 rest on segments 6 in positions toengage the projections 8 of segments 6 when movement of lever 2 isattempted from either of its extreme positions to the other. Each of themagnets 12 also controls a contact 14 which is closed when the magnet isdeenergized, and which opens when the magnet becomes energized. Beforelever 2 can be moved from either of its extreme positions, to which Ihave referred as the normal and the reverse positions', to the other,both of the magnets 12 must be energized to disengage the dogs 10 fromthe projections 8 of the segments 6.

The locks for lever 4 are designated left lock and right lock. Each ofthese locks comprises a segment 7 and an electromagnet 13. Each of thesegments 7 is rigidly attached to, and movable by, shaft 3 of lever 4.Each of the magnets 13- controls a dog 11 which, when the magnet isdeenergized while lever 4 is in its normal position or in either of itsreverse positions, rests on its segment 7 ma positionto engageaprojection 9 of the segment and so arrest movement of the lever. Theright look controls movement of lever a from the normal position to thereverse position shown in dash lines to the right of the normalposition, or from this reverse position back to the normal position,whereas the left lock controls movement of lever a from the normalposition to the reverse posit-ion shown in dash lines to the left of thenormal position, or from this reverse position back to the normalposition. A small partial movement of lever 4 is permitted from eitherof its two reverse positions toward the normal posit-ion before the dog11 of the corresponding electric lock engages the projection 9 of itssegment 7. Lever l must be in one or the other of its extreme reversepositions in order to cause signal 29 or 30, respectively, to indicateproceed, and hence the partial movement of lever 4, which is permittedfrom one of its reverse positions toward its normal position before oneof the dogs 11 engages the projection 9 of its segment 7 causes thesignal which has been indicating proceed to change to the stopindication.

A stick relay, designated by the term signal relay, has a controlwinding 18, and has a pick-up circuit controlled by contact 108 of trackrelay and by contacts 106 and 15 of lever 1. The signal relay has stickcircuits controlled by contact 108 of track relay 20, and by latchcontact 15 or by either contact 116 or 118 of lever 1-.

Normal and reverse switch indication relays are designated by the termsneutral relays No. 1 and No. 2. Each of these relays has control winding19. Both of these rel -*s arecontrolled by contacts 14 of the pri y lockand the secondary lock of lever 2. in addition, relay No. 1 iscontrolled a neutral and a normal polar contact of the polarized relayand by normally closed contact of lever 2. .Relay No. 2 is controlled bya neutral and a reverse polar contact of the polarized relay and bynormally open contact 100 of lever 2.

The circuit for the primary lock of lever 2 in ludes latch contact 17 ofswitch lever 2, back contact 36 of thesignal relay, and normally closedcontact of lever thus insur-' ing that before magnet 12 of the primarylock can become energized, lever 1 must be in its normal position, thesignal relay must he deenergized, and latch contact 1? of twitch lever 2must he closed. '1 he circuit for the secondary lock of lever 2 includeslatch contact 16 of lever 2, back contacts 1? and stop. operates asimilar contact 32 which is closed only when signal 30 is indicatingstop.

For permitting lever 1 to he moved from the normal position to itsreverse position to the right of the normal position, the right lookcludes n'ont contact 61 of neutral relay No. 1, front contact 58 of thesignal relay, and normally closed contact 5 1 of lever For controll ngthe movement of lever 1- from this reverse po. alien to the normalposition, the right look is provided with a'circuit which inc .decont-acts and 31 of signals y, and contact of lever is controlled bycircuits r to those just described-for the right lock.

A switch indicator, here shown as an'elcctric lamp, anddesignated by thereference character 102, is controlled in multiple with lo z magnet 73of slide valve 28. This lamp therefore becomes lighted whenenergy issupplied to the circu t for magnet 1 3 for controlling an operation ofswitch from one of its extreme positions, to which 1 "have referred asthe normal and the reverse positions, to the othe Lamp 102 becomes er:-tingui lied when the source of current disconnected from the circuitforlock magnet 73 upon the completion of an operation of switch 25 from oneof its extreme positions to the other, and hence the extinguishing oflamp 102 indicates that such an operation of switch 25 has beencompleted;

Electric lamps, designated by the reference characters 112 and 113,respectively, serve as indicators in connection with the left lock andthe right lock respectively, of lever 4. When the operator desires toclear one of the signals 29 and 30 he closes latch contact 15 of lever aand holds it closed until the corresponding lamp 112 o 113 becomeslighted. By the lighting of eit r her operator is informed that thecircuit for the corresponding lock magnet 13 of lever 1 has beencompleted through. front contact of, the signal relay, thus permittinglever 1 to be moved to a corresponding reverse position for clearing oneor the other of signals 29 and 30. lhe operator continues to hold latchcontact 15 closed'until he has moved lever & to th desired reverseposition for clearing one of the signals 29 and 80, after which hepermits latch contact 15 to open.

Having thus described, in general, the arrangement, location, andcontrol of the various parts comprising ourinvention, we will now tracein detail the operation of the apparatus.

As shown in the drawings,all parts are in provided with circuit whichinof these lamps, the

lac

indicating stop; and the track circuit shown in the drawings isenergized. lVith the track circuit energized, contacts 51 and 108 oftrack relay 20 are closed. With lever 2 in its normal position, normalcontrol magnet 80 for slide valve 28 is energized by a circuit passingfrom terminal B|-, through wire 77, contact 78 of lever 2, wire 7 9, andthe winding of magnet 80 to terminal B. With magnet 80 energized, pistonmechanism 75 of indication device 67 is holding contact bars 85 and 86of indication device 67 in the positions shown in Fig. 1. With switch 25in its normal position, the contact bars of indication device 27 occupytheir positions also shown; in Fig. 1 With the contacts of indicationdevices 27 and 67 occupying the positions shown in the drawings, thepolarized relay is energized in the normal direction by a circuitpassing from terminal 13+, through wire 93, upper contact bar 89, uppercontact spring 96 of indication device 27 upper wire 95, upper contactbar 85 of device 67, wire 87, winding 21 of the polarized relay, wire88, lower contact bar 85 of device 67, lower wire 95, lower contactspring 96,1ower contact bar 89 of device 27, and wire 94 to terminal l3The polarized relay being energized in the normal direction, neutralrelay No. 1 is energized by a circuit passing from terminal 13+, throughthe front point of contact 22 of the polarized relay, polar contact 98of the polarized relay closed in the left position, wire 43,

contact 42 of lever 2, wire 41., winding 19 of relay No. 1, wire 40,contact 14 ofthe primary lock, wire 39, and contact 14 of the secondarylock to terminal 'B.

We will assume that the operator desires to clear signal 30 for atraliic movement along the main track over switch 25 in its normalposition. He therefore closes latch contact 15 of lever 4, causing apick-up circuit to be completed for the signal relay, passing fromterminal 13+, through contact 108 of trackrelay 20, wire 107, contact106 of lever 4, wire 105, winding 18 of the signal relay, wire 104,latch contact 15 of lever 4, and wire 103 to terminal B. Contact 110 ofthe signal relay, upon becoming closed, completesa stick circuit forthis relay which follows the path just traced for the pick-up circuit asfar as a branch from wire 107, and thence passing through contact 110 ofthe signal relay, a short portion of wire 105, winding 18 of the signalrelay, wire 104, latch contact 15 of lever 4, and wire 103 to terminal Ba The signal relay, upon becoming energized, closed its front contacts68, thereby completing a circuit'for the left lock, passing fromterminal 13+, through the front point of contact 72 of neutral relay N0.1, wires and 69, contact 68 of the signal relay, wire 66, contact 64 oflever 4, wire 63, winding 13 of the left lock, and wire 62 to terminalB. At the same time, indicator lamp 112 becomes lighted by the circuitjust traced for theleft lock as far as con tact 68 of the signal relay,and thence pass ing through wire 1 11, and the filament of lamp 112 toterminal B. On account of lamp 112 becoming lighted, the operator knowsthat he can now move lever 4 to its reverse position to the left.'Meanwhile, he retains latch contact 15 closed until he has moved lever4 to the left reverse position, in which a second sticl; circuit iscompleted for the signal relay which follows the path traced for thefirst stick circuit as far as wire 104, and thence passing through wires115 and 117, contact 118 of lever 4, and wire 119 to terminal B. Theoperator then permits latch contact 15 to open;

Lever 4, upon being moved toits' reverse position, also closes itscontact. 128, thereby completing an operating circuit for signal 30which follows the path already traced for the left lock as far as wire66, and thence passing through wire 127, contact 128 of lever 4, wire129, the mechanism of signal 30, andwire 130 to terminal B'. I The armof signal 30 thereupon becomes operated to the proceed position, openingits contact 32. If, after clearing signal 30, the operator desires toreturn the arm of signal 30 to the stop position before a train entersthe section of track shown in the drawings, he will move lever 4 fromthe left reverse position towards the normal position, to the'positionin which dog 11 of the left lock engages projection 9 of its segment 7.7 Contact 128 opens when lever 4 is moved to this latter position, butcontact 65 remains closed until lever 4 is later moved away from thisposition toward its normal position. Hence, upon the movement of lever 4from its left reverse position to the position in which dog 11 of theleft lock engages projection 9 of its segment, 7, contact 128 of lever 4breaks the circuit for signal 30, causing the arm of signal 30to returnto the stop position. The arm of signal 30, upon reaching the stopposition, again closes its contact 32, thereby completing a secondcircuit for the left lock, passing from terminal 13+, through contact 32of signal 30, wire 125, contact 31 of signal 29, wire 126, contact 65 oflever 4, wire 63, winding 13 of the left lock, and wire62 to terminal 13Magnet 13 of the left lock, being thus energized, lifts dog 11 out ofengagement with projection 9 of its segment7, andthe operator thencompletes the movement of lever 4 to its normal position. Meanwhile, thesignal relay has become deenergized when lever 4, upon being moved fromits left reverse position, opened its contact 118. All parts of theapparatus are therefore again in their normal condition.

We will now assume that the operator again clears signal 30 for atraliic movement over switch 25 in its normal position, as alreadydescribed, and that he then permits signal 30 to continue to'indicateproceed until a train moving toward the left, passes this signal. Atrain, upon passing signal 30, deenergizes track relay 20, therebybreaking the stick circuit for the signal relay at contact 108 of relay20. The signal relay, up0n becoming deenergized, breaks, at itscontact68, the circuit previously traced for signal 30, causing the arm ofsignal 30 to return to its stop position. After the train has passedthrough the track section shown in the drawings, and track relay 20 hasagain become energized, signal 30 will continue to indicate stop onaccount of the signal relay remaining deenergized. The signal relaycannot again become energized until the operator returns lever 4 to itsnormal position thereby closing its contact-106 in the pickup circuitfor the signal relay. On account of contact 32 of signal 30 beingalready closed by the movement of the arm of this signal to its stopposition dueto the deenergization of traclr'relay 20, the'operator canreturn lever 4 to its normal position without lever 4 being arrested byengagement of dog 11 of the left lock with projection 9 of its segment7. Upon the return of lever 4 to its normal position, all parts of theapparatus will be again in their normal condition.

We will next assume that the operator desires to reverseswitch 25 andclear signal 30 for a trailic movement from the main track, over switch25 reversed, to auxiliary track 24. He therefore closes latch contacts16 and 17 before starting the movement of lever 2. lVit-h latch contact17 closed, winding 12 of the primary lock is energized by a circuitpassing from terminal B through wire 33, contact 34 of lever 4,'wire 35,contact 36 of the signal relay, wire 37, latch contact 17 of lever 2,wire 38, and winding 12 ofthe primary lock to terminal B. The primarylock magnet, being thus energized, opens its contact 14, causing neutralrelay No. l to become deenergized, thereby completing a circuit forwinding 12 of the secondary lock passing from terminal 13+, throughcontact 51 of track relay 20, wire 5O,v contact 49 of neutral relay No.2, wire 48, contact 4' of neutral relay No. 1, wire 46, winding 12 ofthe secondary lock, wire 45, and latch contact 16 to terminal Blilagnets 12 of both the primaryand secondary locks for lever 2 beingenergized, the dogs 10 become lifted out of engagement with projections8 of the segments 6, thus upon the completion of this movement, contact83 of lever 2 completes a circuit for the reverse control magnet 81 forslide valve 28, passing from terminal B through wire82, contact 83 oflever 2, wire 84, and the wind-' ing of magnet 81 to terminal 13-. countof the energization of the circuit for magnet 81, piston mechanismdisconnects contact bars 85 of mechanism 67 from wires 87 and 88, andconnects bars 86 with contact springs 97 of indication device 27.Winding 21 of the polarized relay is thus disconnected from terminals13+ and B, and shunting bar 92 of device 27 is connected across winding21 of the polarized relay, through contact springs 97 of device 27,contact bars 86 of device 67,- and wires 87 and 88; At the time of thecompletion of the circuit for magnet 81, a circuit was also completedfor lock magnet 73 of slide valve28, passing from terminal 13+, throughwire 82, contact 83 of lever 2, wire 84, polar contact 23 of thepolarized relay in its normal position, wires 76' and 76, and thewinding of magnet 73 to terminal B-. Upon the deenergization of thepolarized relay, a second circuit is completed for lock magnet 7 3 ofslide valve 28, passing from terminal B through back point of contact 22of the polarized relay, wires 76 and 76, and the winding of magnet 73 toterminal B-. The energization of either circuit for magnet 7 3 causeslamp 102 to become lighted by a circuit which follows either of thepaths traced for magnet 73 as far as wire 76, thence passing through thelower portion of wire 76, and the filament of lamp 102 to terminal B Theenergization of magnets 73 and 81 causes fluid pressure to move thepiston of device 26 to cause mechanism 44 to move switch 25 to itsreverse position. Just as the movement of switch 25 is being completedto its reverse position, mechanism 44 disconnects contact bars 89 ofdevice 27 from contact springs 96', and connects shunting bar 90 acrosssprings 96. Mechanism 44, at the same time, removes shunting bar 92 fromsprings 97, and connects contact bars 91 with springs 97, therebycompleting a circuit for energizing the polarized relay in the reversedirection, passing from terminal 13+, through the upper contact bar 91,upper contact spring 97, upper contact bar 86 of device 67., wire 88,

winding 21 of the polarized relay, wire 87 On acto its normalposition.

passing from terminalB through the front point of contact 22 of thepolarizedrelayf polar contact 98 of the polarized relay in its reverseposition, wire 99, contact 100 of lever 2, wire 101, winding 19 ofneutral relay- N o. 2, wire 40, contact 14 of the primary lock, wire 39,and contact 14. of the secondary lock to terminal 13 The polarizedrelay, upon becoming energized in the reverse direction, first opens, atits contact 23, the circuit first traced for lock magnet 73 of slidevalve 28, and then, by opening contact 22 at its back point, breaks thesecond circuit for lock magnet7 3. Upon the opening of both the circuitsfor lock magnet 73, lamp 102, which is controlled in multiple with lockmagnet 73, becomes extinguished, thereby indicating to theoperator thecompletion of the operation of switch 25 to its reverse po sition. i

- The operator will now close latch contact 15 of lever l for energizingthe signal relay as previously described. Lever 4, upon now being movedto the left reverse position,

' completes a second circuit for signal which is the same'as the circuitpreviously traced for signal 30 except that it passes from terminal 13+,through the back point of contact 72v of neutral relay No. 1, thencethroughwire 74, and contact 71 of neutral relay N o. 2, to wire 69. Thearm of signal 30, upon leaving its stop position, again opens itscontact 32. I

We will now assume that the operator again returns the arm of signal 30to its stop position, preparatory to returning switch 25Preparatorytoreturning switch 25 to its normal position, the operatorcloses latch contacts 16 and 17before starting the movement of lever 2from its reverse to its normal position. The primary lock magnet- 12thereupon becomes energized as previously described. The primary lockmagnet, upon becoming energized, opens its contact-14, thereby breakingthe circuit for neutral relay No. 2, and causing the secondary lockmagnet to become energized by its circuit previously traced.

The operator then returns lever 2 to its normal position, therebybreaking the circuit for magnet 81 and again completing the circuitpreviously traced for magnet of slide valve 28. At the same time, athirdoircuit is completed for lock magnet 73 of slide valve 28, passingfrom terminal 13+, through wire 77, contact 78 of lever 2, wire 79,polar contact 23 of the polarized relay in its reverse position, wires 76 and 76, and the winding of magnet 73 to terminal B Upon theenergization of the circuitfor magnet 80, piston mechanism 75disconnects contact bars 86 of device 67 from contact-springs 97 ofdevice 27, and. again connects contact bars with wires 87 and88, therebycausing shunting bar 90 of device 27 to be connected across winding 21of the polarized relay, through contact springs 96 of device 27, wires95, contact bars 85 of device 67, and wires 87 and 88. Upon the'deenergization of the polarized relay, the second circuit for magnet 73again be: comes energized. V

WVith-magnets 80 and 73 energized, the pis ton mechanism of device 26operates mechanism 44: to return switch 25 from its reverse to itsnormal position. Just as this operation is being completed, mechanism4C4: removes shunting bar 90 from springs 96 of device 27 and againconnects contact bars 89 with contact springs 96, and also removescontact bars 91 from springs97 and connects shunting bar 92 with springs97 of device 27. The circuit for energizing the polarized relay in thenormal direction, previously traced, is thereby again completed, causingthe polarized relay to return its polar contacts 23 and 98 to theirnormal position, and to close its contact 22 at the front point. Thepolarized relay, upon moving its polar contact 23 away from its reverseposition, breaks the third circuit for lock magnet 73, and upon openingcontact 22 at the back point, opens the second circuit for magnet 73.All circuitsfor magnet 73 being now deenergized, lamp 102 again becomesextinguished, indicating to the operator the completion of the return ofswitch 25 to its normalposition.

We have described in detail, for a few typical conditions, the operationof the apparatus embodying our invention. From those descriptions andfrom the preceding general description, the operation of the apparatusfor every other possible condition will be readily understood byreference to the drawings.

From the foregoing descriptions and the accompanying drawings, it willbe clear that levers 2' and 4 are not mechanically interlocked but thatthey are interlocked electrically by means of the electric locks forthese levers and by the control circuits for those electric locks.

Apparatus embodying our invention also eliminates the well knownindication locking of the switch lever which prevents complete movementof aswitch lever to the reverse or the normal position until acorresponding movement of the switch has been completed. I

This permits the operator to make a complete movement of the switchlever from either of its extreme positions to the other without waitingat an intermediate indication position for the switch to complete itsmovement. The control accomplished by such indication locking isprovided by the electric lock for the signal lever which'prevents amovement of the signal lever to clear .a signal until the switch overwhich the sig- Lit;

1,sso,ose

nal governs has been operated to the proper position.

Another feature provided by apparatus embodying our invention is thejoint control of the polarized relay by the devices 27 and 67. Thiscontrol of the polarized relay insures correspondence between theposition of the switch and the condition of the switch control apparatuswhich is located at the switch. The signal lever cannot be operated forclearing a signal until one of the neutral relays No. l or No. 2corresponding to the direction of energization of the polarized relay isenergized. i

Although we have herein shown and described only one form of electricinterlocking machines embodying our invention, it is understood thatvarious changes and modifications may be made therein within the scopeof the appended claims without departing from the spirit and scope ofour invention.

Having thus described our invention, what we claim is:

.1. In combination, manually controllable signal operating mechanism,manually controllable switch operating mechanism, and mutuallymechanically independent electric interlocking means for said mechanismscontrolled by the operation of signals and a switch operated by saidmechanisms for pre-' venting manual operation of the mechanisms underpredetermined conditions without mechanical interlocking means.

2. In combination, manually controllable signal operating mechanism,manually controllable switch operating mechanism, said mechanisms havinga plurality of diiierent operated positions, and mutually mechanical- 1yindependent electric interlocking means interconnected with saidmechanisms for interlocking said mechanisms in a predetermined mannerfor all positions of said mechanisms, said interlocking means havingportions controlled by switch and signal operation to controlinterlocking under predetermined conditions. i i

3. In combination, manually controllable signal operating mechanism, arailway track switch, manually controllable switch operating mechanismfor said switch, mutually mechanically independent primary electricinterlocking means'for said mechanisms, secondary electric interlockingmeans for said mechanisms, means controlled by said switch forcontrolling said secondary interlocking means, and means controlled bysaid primary and secondary interlocking means for controlling saidsignal and switch mechanisms.

4. In combina ion, manually controllable signal operating mechanism, arailway track switch, manually controllable switch operating mechanismfor said switch, mutually mechanically independent primary electricinterlocking means for said mechanisms, secondary electric interlockingmeans for said switch mechanism interdependent for operation on saidprimary means, and means controlled by said switch for controlling saidprimary and secondary interlocking means.

5. In combination, manually controllable signal. operating mechanism,manually controllable switch operatingmechanism,independentelectromagnetic locking means for said mechanisms,electrically operated controlling means for said locking means, andswitch and signal controlled electric means or governing the operationof both the lock ing means and controlling means to provide interlockingof said mechanisms in a predetermined manner.

6. In combination, manually controllable signal operating mechanism,manually controllable switch operating mechanism, independentelectromagnetic locking means for each of said mechanisms, electricallyoperated controlling means for said locking means, switch and signaloperated electric means for controlling the operation of both theaforementioned means to produce interlocking of said mechanisms in apredetermined manner, and pneumatic means for controlling saidelectrically operated control means in conjunction with mechanicalswitch operating means forming part of said switch operating mechanism.7 r

7. @perating mechanism for a railway switch and railway signals,comprising a manually operable control lever for the signals, a manuallyoperable control lever for the switch mechanically independent of thecontrol lever for the signals, electric means controlled by said leversfor controlling the operation of the signals and switch in accordancewith the operation of the respective levers, and electric interlockingmeans for interlocking the manual operation of said control levers, saidelectric interlocking means having control devices associated with theswitch and signals for operation thereby for controlling interlocking ofthe control levers in a predetermined manner.

8. Operating mechanism for a railway switch and railway signalscomprising manually operable control lever for the signals, a manuallyoperable control lever for the switch, electric operating means for theswitch and signals operated in accordance with the operation of thecontrol levers, and electricinterlocking means for said control leversincluding electro-magnetic latching means for said levers,electro-magnetic relays for controlling the operation of said latchingmeans, and means associated with the switch and signals for governingthe operation of the relays.

3. An electro-pneumatic interlocking machine comprising a manuallyoperable control lever for signals, a manually operable control leverfor a switch, electric means for control operating pneumaticoperatingmeans for the switch, an electric operated means for thesignals adapted to operate said switch and signals in accordance withthe operation of the control levers, and electric interlocking means fors aid control levers, including electrically controlled lock magnets,relays interconnected in circuit with said lock mag nets and a source ofenergy having connec-. tion controlled by the operation of said signaland switch control levers, and additional controllingmcans operatedthrough the movement of the s itch and signal. for additionallycontrolling the operation of said relays. v w.

10. An electro-pneumatic interlocking machine comprising a manuallyoaerabie control lever for signals, a manually operable lever for aswitch, pneumatic mecha nism for operating the switch, electric meanscontrollable by the operation of the signal and switch control leversoperable for effecting the operation of the signal and the pneumaticmeans for operating the switch, electric interlocking means for saidcontrol levers having electrically operated lock mechanism for saidlevers, automatic electrically oper ated contact devices for controllingthe circuit to said locking mechanism, means operated by said controllevers for controlling the operation of said contact devices in apredetermined 1nanner,and switch and signal operated means forcontrolling the automatic operation of said contact devices in apredetermined manner.

11. In combination, manually controllable si nal operating mechanism,manually controllable switch operating mechanism, mutually mechanicallyindependent interlocking means for both of said mechanisms, and anelectrically operated signal controlled by the operation of the switchfor indicating the completion of an operation of said switch.

12, In combination, manuallycontrollable signal operating mechanism, amanually operable control lever for a switch, switch operating means forsaid switch, electric interlocking means for the signal operatingmechanism and the manually operable control lever. and means forcontrolling the said interlocking means controlled by the operation ofboth the switch operating mechanism and the operation of the switch.

13. An interlocking mach ne comprising a manually operable control leverfor signals, a manually operable control lever for a switch,interlocking means for said control lever, pneumatic operating means forthe switch controlled by said manually operable switch control lever,electric control means for the interlocking means operated by theswitch, and electric operated means controlling the interlockingmeansoperated by the pneumatic switch operating mechanism.

14. Operating mechanism for a railway switch and railway signals,comprising a manually operable control lever for the signals, a manuallyoperable control lever for the switch, electric means controlled by saidlevers for effecting the operationof the signals and switch inaccordance with the operation. of the respective levers, electricinterlocking means for interlocking the manual operation of the controllevers, a polarized relay for controlling the operation of said electricinterlocking means, switch operated means, and means operated by theoperating mechanism for the switch cooperating for controlling theoperation of the polarized relay.

15. Railway interlocking apparatus, comprising an interlocking framecontaining a plurality of levers, electric locks for said levers,an'energizing circuit for a lock for each lever controlled by anothersaid lever, electrically operated means in said energizing circuit forindependently controlling said lock, and means, the operation of whichis controlled by said levers, for governing operation of the last namedmeans in a predetermined manner.

'16; In combination, a manually controllable tralfic governing device, astick relay having a pickup and a stick circuit one of which iscontrolled by traiiic conditions and the other of which is controlled bysaid device, and means controlled-by said relay for controlling saiddevice.

17. In combination, a manually controllable trafiic governing device, astick relay having a pick-up and a stick circuit one of which iscontrolled by trafiic conditions and by said device and the other ofwhich is controlled by trafiic conditions, and means controlled by saidrelay for controlling said device.

18. In combination, a lever, means controlled by said lever foroperating a railway signal, a second lever, a railway track switchmechanism controlled by said second lever and having a normal and areverse extreme position, and electrically movable means engaging saidfirst lever and controlled by said switch mechanism for permittingmovement of said first lever when and only when said switch mechanismoccupies one of said extreme positions.

19. In combination, a railway track switch mechanism, a switch lever,means controlled by said lever for operatingsaid switch mechanism, asignal lever for operating a railway signal, electrical means controlledby said signal lever for cont-rolling said switch lever, andelectrically movable means engaging said signal lever and controlled bysaid switch lever and by said switch mechanism for controlling saidsignal lever.

20. In combination, a railway track switch mechanism, control means forsaid switch mechanism, a polarized indication relay having a polarcontact which when said relay is deenergized continues closed in aposition corresponding to the last previous direction 21. Incombination, a circuit for control-- ling a railway tratfic governingdevice, a manually operable device, a second manually operable device, arelay included in said circuit in series with means controlled by saidrelay, means controlled by said first manually operable device connectedin multiple with said first means in said circuit, and means controlledby said second manually operable device included in said circuit.

22. In combination, a stretch of railway track including a switch andprovide-d with a track circuit, a signal governing trafic movement-sover said switch, a manually operable device, a second manually operabledevice, electrically operable means controlled by saidfirst device forcontrolling said second device, electrically operable means controlledby said second device and by said track circuit for controlling saidfirst device, means controlled by said second device for controllingsaid switch, and means controlled by said first device for controllingsaid signal.

23. In combination, a stretch of railway track including a switch andprovided with a track circuit, a signal governing traflic movements oversaid switch, a manually operable device, a second manually operabledevice, electrically operable means controlled by said first device forcontrolling said second device, an electrically operable instrumentcontrolled by said second device and by said track circuit forcontrolling said first device, means controlled by said first device forcontrolling said switch, and means controlled by said second device forcontrolling said signal.

24. In combination, a railway track switch, a signal governing tratficmovements over .said switch, a manually operable device, a

second manually operable device, electrically operable means controlledby said signal and by said first device for controlling said seconddevice, electrically operable means controlled by said switch and bysaid second device for controlling said first device, means controlledby said first device for controlling said switch, and means controlledby said second device for controlling saidsignal.

25., In combination, a railway track switch, I

a signal governing trafiic movements over said switch, a manuallyoperable device, a second manually operable device, electricallyoperable means controlledby said signal and by said first device forcontrolling said sec 0nd device, electrically operable means controlledby said second device for controlling said first device, meanscontrolled by said first device for controlling said switch, and meanscontrolled by said second device for controlling said signal.

26. 'In combination, a railway track switch,

a signal governing trafiic movements over said switch, a manuallyoperable device, a second manually operable device, electricallyoperable means controlled by said first de vice for controllingsaidsecond device, elec-' tricaliy operable means controlled by saidswitch and by said second device for controlling said first device,means controlled by said first device for controlling said switch, andmeans controlled by said second device for controlling said signal.

27. In combination, a railway track switch, a signal governing traflicmovements over said switch, a manually operable device, a secondmanually operable device, electrically operable means controlled by saidfirst device tor controlling said second device, electrically operablemeans controlled by said switch and by said second device for controlling said first device,means controlled by said first device forcontrolling said signal, and means controlled by said second device forcontrolling said switch. i

28. In combination, a railway track switch, a lever having anormal and areverse position for controlling said switch, a contact controlled bysaid lever and arranged to close when said lever is moved to its normalposition but to open when said lever is moved to its reverse position, asecond contact controlled by said lever and arranged to close when saidlever is moved to its reverse position but to open when said lever ismoved to its normal position, a third contact controlled by said switchand arranged to be closed when said. switch occupies its normalposition, a fourth contact controlled by said switch and arranged to beclosed when said switch occupies its reverse position, normal indicationmeans, reverse indication means, a circuit including said first andvthird contacts in series for controlling said normal-indication means,and a circuit including said sec- 0nd and fourth contacts inseries forcontrolling said reverse indication means.

29. In combination, a railway trackswitch, 7

a leverhaving a normal and a reverse position for controlling saidswitch, a contact controlled by said lever and arranged to remain closedwhen said lever occupies its normal contact controlled by saidswitch andarranged to close when said switch 1s moved to its normal position, afourth contact controlled bysaid switchand arranged to close ing trafficmovements in opposite directions respectively over said stretch, a stickrelayfor said first signal, a contact which stays open except whenmanually held closed, a pick-up circuit for said stick relay controlledby said contact, a stick circuit for said stick relay controlled bytraiiic conditions, means controlled by said stick relay for controllingsaid first signal, a circuit for controlling said second signal, andmeans controlled by said stick relay for opening said control circuit 25v for said second'signal. v v 31. In combination, a stretch of railwaytrack, a first and a second signal for governing tratlic movements inopposite directions respectively'over said stretch, a stick relay, a

manually operable device, a pick-up and a stick circuitforsaid relay oneof which is concontrolled by said manually operable device and the otherof which is controlled by traffic in saidstretch, and means controlledby said relay for controlling said first and second signals. p

- 32-11'1- combination, a stretch of railway track, a: first and asecond signal for governingtraffic movementsin opposite directionsrespectively over said stretch, a stick relay, a. manually operabledevice, apick-up and a stick circuit for said relay one of which iscontrolled by said manually operable device and the other of which iscontrolled bytraific in said stretch, and means including front contactsot said relay for controlling said first andsecond signals; V

33. In combination, a stretch of railway track,-a first and asecond'signal for govern- 7 ing traffic-movements in opposite directionsrespectively over said stretch, a track circuit for said stretch, astick relay, a manually operable device,. a pick-up circuit for saidrelay includingsaid manually operable device, a stick circuit for'saidrelay controlled by said track circuit, and means controlled by: said.relay for'controlling said first and second signals.

" 34. In combination, a stretch of railway track, afirst anda-second'signalfor governing traflic movements in opposite directionsrespectively over said stretch, a track circuit for said stretch, astick relay, a manually operable device, at pick-up circuit for saidrelay controlled by said track circuit, a stick,

circuit for said relay including said manually operable device, andmeans controlled bysaid relay for controlling said first and secondsignals.

revers'eposition with said control means in a v corresponding condition,a plurality of signals for governing traflic movements over said switch,and means controlled by said indication relay for controlling sa1dsignals.

36. In ccmbinatioma railway track switch mechanism, a manually operablecontrol lever having a normal and a-reverse position, a normal and areversecontrolvmagnet, a lock magnet, a polarized indication relayhaving normal polar contact and a reverse polar contact one or the otherof which is closed according as said relay becomes energized'in thenormal or the reverse direction respecively, means controlled by saidswitch for energizing said rela'y'in the normal or the reverse directionaccording as said switch is operated to the normal or the reverseposition respectively, means controlled by said lever inits normalposition for controlling said normal magnet, means controlled by saidlever in its reverse position for controlling said reverse magnet, meanscontrolledby said reverse polar contact for controlling. said lockmagnet if said'lever is operated to its normal position, meanscontrolled by said normal polar contact for controlling said lock magnetit said lever is operated to its-reverse'position, and meanscontrolledby said normal and reverse control magnets and by said lock magnet foroperating saidswitchtoits normal or lts-reverse posltion accordingassaid normal or said reverse magnetis energized and if said lock magnetis energized;

Intestimony whereof we aifiX our signa-

